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<title>KIND Type Parameters (The GNU Fortran Compiler)</title>

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<span id="KIND-Type-Parameters-1"></span><h3 class="section">4.1 KIND Type Parameters</h3>
<span id="index-kind"></span>

<p>The <code>KIND</code> type parameters supported by GNU Fortran for the primitive
data types are:
</p>
<dl compact="compact">
<dt><code>INTEGER</code></dt>
<dd><p>1, 2, 4, 8*, 16*, default: 4**
</p>
</dd>
<dt><code>LOGICAL</code></dt>
<dd><p>1, 2, 4, 8*, 16*, default: 4**
</p>
</dd>
<dt><code>REAL</code></dt>
<dd><p>4, 8, 10*, 16*, default: 4***
</p>
</dd>
<dt><code>COMPLEX</code></dt>
<dd><p>4, 8, 10*, 16*, default: 4***
</p>
</dd>
<dt><code>DOUBLE PRECISION</code></dt>
<dd><p>4, 8, 10*, 16*, default: 8***
</p>
</dd>
<dt><code>CHARACTER</code></dt>
<dd><p>1, 4, default: 1
</p>
</dd>
</dl>

<p>* not available on all systems <br>
** unless <samp>-fdefault-integer-8</samp> is used <br>
*** unless <samp>-fdefault-real-8</samp> is used (see <a href="Fortran-Dialect-Options.html">Fortran Dialect Options</a>)
</p>
<p>The <code>KIND</code> value matches the storage size in bytes, except for
<code>COMPLEX</code> where the storage size is twice as much (or both real and
imaginary part are a real value of the given size).  It is recommended to use
the <a href="SELECTED_005fCHAR_005fKIND.html">SELECTED_CHAR_KIND</a>, <a href="SELECTED_005fINT_005fKIND.html">SELECTED_INT_KIND</a> and
<a href="SELECTED_005fREAL_005fKIND.html">SELECTED_REAL_KIND</a> intrinsics or the <code>INT8</code>, <code>INT16</code>,
<code>INT32</code>, <code>INT64</code>, <code>REAL32</code>, <code>REAL64</code>, and <code>REAL128</code>
parameters of the <code>ISO_FORTRAN_ENV</code> module instead of the concrete values.
The available kind parameters can be found in the constant arrays
<code>CHARACTER_KINDS</code>, <code>INTEGER_KINDS</code>, <code>LOGICAL_KINDS</code> and
<code>REAL_KINDS</code> in the <a href="ISO_005fFORTRAN_005fENV.html">ISO_FORTRAN_ENV</a> module.  For C interoperability,
the kind parameters of the <a href="ISO_005fC_005fBINDING.html">ISO_C_BINDING</a> module should be used.
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